Q1: An article is purchased for Rs. 450 and sold for Rs. 500. Find the gain percent.
Ans:
Gain = SP - CP = 500 - 450 = 50.
Gain% = (Gain/CP) × 100 = (50/450) × 100 = 100/9 % ≈ 11.11%.
Q2: A man sold a fan for Rs. 465. Find the cost price if he incurred a loss of 7%.
Ans:
Loss% = 7% so SP = 93% of CP.
CP = (100/93) × SP = (100/93) × 465 = 500.
Therefore, the cost price of the fan = Rs. 500.
Q3: In a transaction, the profit percentage is 80% of the cost. If the cost further increases by 20% but the selling price remains the same, how much is the decrease in profit percentage?
Ans:
Assume CP = Rs. 100.
Profit = 80% of 100 = Rs. 80, so SP = CP + Profit = 100 + 80 = Rs. 180.
If cost increases by 20% → New CP = 120.
New profit = SP - New CP = 180 - 120 = Rs. 60.
New profit% = (60/120) × 100 = 50%.
Decrease in profit percentage = 80% - 50% = 30 percentage points.
Q4: A man bought some toys at the rate of 10 for Rs. 40 and sold them at 8 for Rs. 35. Find his gain or loss per cent.
Ans:
Cost price of 10 toys = Rs. 40 → CP of 1 toy = Rs. 40/10 = Rs. 4.
Selling price of 8 toys = Rs. 35 → SP of 1 toy = 35/8 = Rs. 4.375.
Gain per toy = SP - CP = 4.375 - 4 = 0.375 = 3/8.
Gain% = (Gain/CP) × 100 = (0.375/4) × 100 = 9.375%.
Q5: The cost price of 10 pens is the same as the selling price of n pens. If there is a loss of 40%, approximately what is the value of n?
Ans:
Let CP per pen = c and SP per pen = s.
Given: CP of 10 pens = SP of n pens → 10c = n s.
Loss 40% means s = 60% of c = 0.6c.
So 10c = n × 0.6c → 10 = 0.6 n → n = 10/0.6 = 100/6 ≈ 16.67 ≈ 17.
Q6: A dishonest merchant sells his grocery using weights 15% less than the true weights and makes a profit of 20%. Find his total gain percentage.
Ans:
Let the cost price of 1 kg = Rs. 100 (assume for easy calculation).
Marked selling price for 1 kg with 20% profit = 120% of 100 = Rs. 120.
But using weights 15% less, when he sells "1 kg" he actually gives only 85% of 1 kg = 0.85 kg.
Cost of the 0.85 kg he gives = 0.85 × 100 = Rs. 85.
Profit on that sale = SP - actual cost = 120 - 85 = Rs. 35.
Total gain% = (Profit / Actual cost) × 100 = (35/85) × 100 ≈ 41.176% ≈ 41.18%.
Q 7: A man bought two bicycles for Rs. 2500 each. If he sells one at a profit of 5%, then how much should he sell the other so that he makes a profit of 20% on the whole?
Ans:
Total cost for two = 2500 + 2500 = Rs. 5000.
Required total selling price for 20% overall profit = 120% of 5000 = Rs. 6000.
He sells one at 5% profit → SP₁ = 105% of 2500 = 1.05 × 2500 = Rs. 2625.
Required SP for the other bike = 6000 - 2625 = Rs. 3375.
Profit% on the second bike = [(3375 - 2500)/2500] × 100 = (875/2500) × 100 = 35%.
Q8: A shopkeeper allows a discount of 10% on the marked price and still gains 17% on the whole. Find at what per cent above the cost price did he mark his goods.
Ans:
Let CP = Rs. 100.
Since he gains 17%, SP = Rs. 117.
SP = 90% of marked price (after 10% discount) → 0.9 × Marked price = 117.
Marked price = 117 / 0.9 = 130.
Marked above cost = (130 - 100)/100 × 100 = 30%.
Q 9: A shopkeeper offers a discount of 20% on the selling price. On a special sale day, he offers an extra 25% off coupon after the first discount. If the article was sold for Rs. 3600, find
Ans:
Let the marked price be x.
After the first discount of 20%, the price becomes 80% of x. After an extra 25% off, the final price = 75% of that.
So final price = 75% of 80% of x = 0.75 × 0.8 × x = 0.6 x = 3600 → x = 3600/0.6 = 6000.
Thus, marked price = Rs. 6000.
If final SP = Rs. 3600 and this gives an overall profit of 80%, then SP = 180% of CP → CP = SP/1.8 = 3600/1.8 = Rs. 2000.
Q10: A person buys 60 oranges at the rate of Rs. 21 per dozen and sells them at the rate of Rs.24 per dozen.
Ans: CP of 1 dozen oranges = 21.
Number of dozens in 60 oranges = 60/12 = 5 dozen.
CP of 60 oranges = 21 × 5 = Rs. 105.
SP of 1 dozen = 24 → SP of 5 dozen = 24 × 5 = Rs. 120.
Profit = SP - CP = 120 - 105 = Rs. 15.
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